#include<iostream>
#include<cmath>
#include<cstdio>
using namespace std;
int main(){
    int a,b,c;
    while(cin>>a>>b>>c){
        int l=c/b;
        if(c%b)l++;
        if(l>a)cout<<0<<endl;
        else cout<<a-l<<endl;
    }
    return 0;
}
